You may be able to find some free prayer card templates on the web as you do your searches. Keep in mind however, that most anything that is free has some limits. For example, the prayer card design may not contain a background image but may only have the text formation. Then they leave the background design up to you to insert or add.
If that is important to you, then this option may not be worth doing. If you have sufficient time and are able to devote a little more creativity to the project, a free prayer card template is the answer for you. Often its choosing between something cost effective or free in this case, and the amount of time you have to devote to this project.
You can also ask a family member or friend to help you out, perhaps someone who is more skilled and can get the job done quickly. Then using a free template is ideal. Prayer card templates have two pages within the document, the front and the back side. They also come in multiples of eight on a page for the traditional sizing and for a smaller version, they can come in multiples of ten.
Decide which is your best solution and then do your search for the template online. This way you can stay focused on your needs. The traditional size will hold more text than the smaller version which is about the size of a business card. Although very convenient in size, it can hold half the text the larger, traditional size does.